MODIFICATIONS OF CELL-CYCLE INDUCED BY DPR, A NEW PLATINUM-TRIAMINE COMPLEX CONTAINING PROCAINE

cis-diamminechloro-[2-(diethylamino)ethyl 4-amino-benzoate, N4]-chlori deplatinum(II) monohydrochloride monohydrate (DPR) is a new platinum-t riamine complex containing as ligand the local anesthetic procaine. In this study DPR was compared to the parent compound cisplatin (cis-DDP ) in order to study the influence of both molecules on the cell cycle phases, and particularly on the induction of apoptosis. P388 murine le ukemic cells were used as cellular model, and were exposed in vitro to either compound, continuously for 24 hours. At the end of the incubat ion, the thymidine uptake, the trypan blue dye exclusion assay, and th e flow cytometry were assessed. Both the cytotoxic activity and the in hibition of DNA synthesis evaluated after 24 h incubation with DPR or cis-DDP were comparable. Moreover, cell cycle was modified in a compar able manner by both molecules. In particular the induction of the apop totic effect was similarly induced by the same concentrations of the c ompounds and time exposure. In conclusion, DPR and cis-DDP seem to hav e a similar effect on the cell cycle of P388 leukemic cells and partic ularly on the induction of the programmed cell death.